Temporal dynamics of verbal object comprehension.

Knowledge of the stage composition and the temporal dynamics of human cognitive operations is critical for building theories of higher mental activity. This information has been difficult to acquire, even with different combinations of techniques such as refined behavioral testing, electrical recording/interference, and metabolic imaging studies. Verbal object comprehension was studied herein in a single individual, by using three tasks (object naming, auditory word comprehension, and visual word comprehension), two languages (English and Farsi), and four techniques (stimulus manipulation, direct cortical electrical interference, electrocorticography, and a variation of the technique of direct cortical electrical interference to produce time-delimited effects, called timeslicing), in a subject in whom indwelling subdural electrode arrays had been placed for clinical purposes. Electrical interference at a pair of electrodes on the left lateral occipitotemporal gyrus interfered with naming in both languages and with comprehension in the language tested (English). The naming and comprehension deficit resulted from interference with processing of verbal object meaning. Electrocorticography indices of cortical activation at this site during naming started 250-300 msec after visual stimulus presentation. By using the timeslicing technique, which varies the onset of electrical interference relative to the behavioral task, we found that completion of processing for verbal object meaning varied from 450 to 750 msec after current onset. This variability was found to be a function of the subject's familiarity with the objects.

[1]  Alfonso Caramazza,et al.  Theory and methodology in cognitive neuropsychology: A response to our critics , 1988 .

[2]  M. Posner,et al.  Scalp electrical potentials reflect regional cerebral blood flow responses during processing of written words. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[3]  John C. Marshall,et al.  Idealisation meets psychometrics: The case for the right groups and the right individuals , 1988 .

[4]  John Hart,et al.  Neural subsystems for object knowledge , 1992, Nature.

[5]  G. Klem,et al.  Extraoperative Cortical Functional Localization in Patients with Epilepsy , 1987, Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society.

[6]  John Hart,et al.  Delineation of single‐word semantic comprehension deficits in aphasia, with anatomical correlation , 1990, Annals of neurology.

[7]  Conrad V. Kufta,et al.  Event-related desynchronization and movement-related cortical potentials on the ECoG and EEG. , 1994, Electroencephalography and clinical neurophysiology.

[8]  R. Lesser,et al.  Selective Interference with the Representation of Size in the Human by Direct Cortical Electrical Stimulation , 1992, Journal of Cognitive Neuroscience.

[9]  P. Starreveld,et al.  Time-course analysis of semantic and orthographic context effects in picture naming. , 1996 .

[10]  Glyn W. Humphreys,et al.  Cascade processes in picture identification , 1988 .

[11]  H. Lüders,et al.  Basal temporal language area. , 1991, Brain : a journal of neurology.

[12]  Steven L. Small,et al.  Distributed representations of semantic knowledge in the brain. , 1995, Brain : a journal of neurology.

[13]  T. Shallice.  Specialisation within the semantic system , 1988 .

[14]  G. Miller,et al.  Language and Perception , 1976 .

[15]  G. Pfurtscheller,et al.  Event-related cortical desynchronization detected by power measurements of scalp EEG. , 1977, Electroencephalography and clinical neurophysiology.

[16]  B Milner,et al.  THE ROLE OF EARLY LEFT‐BRAIN INJURY IN DETERMINING LATERALIZATION OF CEREBRAL SPEECH FUNCTIONS , 1977, Annals of the New York Academy of Sciences.

[17]  Alfonso Caramazza,et al.  Mechanisms for accessing lexical representations for output: Evidence from a category-specific semantic deficit , 1991, Brain and Language.

[18]  G. McCarthy,et al.  Language-related field potentials in the anterior-medial temporal lobe: II. Effects of word type and semantic priming , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[19]  Adrian F. M. Smith,et al.  Hierarchical Bayesian Analysis of Changepoint Problems , 1992 .

[20]  N. Thakor,et al.  Determination of current density distributions generated by electrical stimulation of the human cerebral cortex. , 1993, Electroencephalography and clinical neurophysiology.

[21]  C. Li,et al.  Cortical intracellular synaptic potentials and direct cortical stimulation. , 1962, Journal of cellular and comparative physiology.

[22]  Leslie G. Ungerleider,et al.  Neural correlates of category-specific knowledge , 1996, Nature.

[23]  Karl J. Friston,et al.  Distribution of cortical neural networks involved in word comprehension and word retrieval. , 1991, Brain : a journal of neurology.

[24]  B. Gordon,et al.  Object shape processing in the visual system evaluated using functional MRI , 1997, Neurology.

[25]  H. Kucera,et al.  Computational analysis of present-day American English , 1967 .

[26]  H A Whitaker,et al.  The bilingual brain. , 1978, Archives of neurology.

[27]  G. Mathern,et al.  Epilepsia , 1991, NEURO FUNDAMENTAL.

[28]  G. Humphreys,et al.  Visual object processing in optic aphasia: a case of semantic access agnosia , 1987 .

[29]  N. Reid,et al.  Likelihood , 1993 .

[30]  G A Ojemann,et al.  Electrocorticographic (ECoG) correlates of language. I. Desynchronization in temporal language cortex during object naming. , 1989, Electroencephalography and clinical neurophysiology.

[31]  P. Berg,et al.  A fast method for forward computation of multiple-shell spherical head models. , 1994, Electroencephalography and clinical neurophysiology.

[32]  T. Allison,et al.  Word recognition in the human inferior temporal lobe , 1994, Nature.

[33]  P. McCullagh,et al.  Generalized Linear Models , 1992 .

[34]  Richard D. Hichwa,et al.  A neural basis for lexical retrieval , 1996, Nature.

[35]  Leslie G. Ungerleider,et al.  Discrete Cortical Regions Associated with Knowledge of Color and Knowledge of Action , 1995, Science.

[36]  B. Gordon.  Subjective frequency and the lexical decision latency function: Implications for mechanisms of lexical access. , 1985 .

[37]  E. Kaplan,et al.  The Boston naming test , 2001 .

[38]  L. Squire,et al.  Structure and function of declarative and nondeclarative memory systems. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[39]  J. Kounios.  On the continuity of thought and the representation of knowledge: Electrophysiological and behavioral time-course measures reveal levels of structure in semantic memory , 1996, Psychonomic bulletin & review.

[40]  M. Metz-Lutz.  Handbook of neuropsychology, Vol 6 et 7, Rapin I, Segalowitz SJ (Eds.). Elsevier (1992) , 1993 .

[41]  Leslie G. Ungerleider,et al.  Object vision and spatial vision: two cortical pathways , 1983, Trends in Neurosciences.

[42]  G A Ojemann,et al.  Individual variability in cortical localization of language. , 1979, Journal of neurosurgery.

[43]  Richard S. J. Frackowiak,et al.  Functional anatomy of a common semantic system for words and pictures , 1996, Nature.

[44]  W. Levelt,et al.  Speaking: From Intention to Articulation , 1990 .

[45]  G. Cascino,et al.  Commentary: How Has Neuroimaging Improved Patient Care? , 1994, Epilepsia.